Why are some sensors showing lower battery than others?
The battery indicator displays the voltage, not the capacity. Cooler temperatures can cause the voltage to drop, but this does not reflect a decrease in capacity. If the voltage is above 2.6 to 2.7 and no 'low battery' alarms are issued, the sensor is functioning properly. Given that the sensors have a battery life of up to ten years, the battery level is generally not a concern.